Shaft for roasting-furnaces.



D. BA'IRD.

SHAFT FOR ROASTING FURNACES.

APPLICATION FILED IULY 3. |915.

Patented Apr. 9,1918;

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A D'UDLEY IBAIRD, OF BERKELEY, CALIFORNIA, ASSIGNOR TO GENERAL CHEMICAL- COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

SHAFT FOR ROASTING-FURNACES.

Specification of Letters Patent.v

Patented Apr. 9, i918.

Application-filed July 3, 1915. Serial No. 37,874.

To all whom t may concern Be it known that I, DUDLEY BAI'RD, a citinew and useful Improvements in Shafts forf Roasting-Furnaces, of which the following, takenin connection with the accompanying drawings, is a specification.

My invention relates to furnaces, especially such as are'usedfor roasting ores, and such as are'provided with superposed stationary hearths upon which the ore is stirred and distributed by rakes or plows aiixed to arms, said arms being in turn affixed to and rotatable with a central vertical shaft which extends through central apertures in the hearths and is rotated by any suitable mechanism.

More particularly my invention relates to the central, rotatable shafts of such furnaces, of th rtype in which longitudinally disposed passages are provided lfor conducting a cooling medium' to and from the' rabble arms through a plurality of longitudinally spaced and angularly disposed sets of rabble arm inlet and outlet ports or apertures, and an object of my invention is to produce a shaft in which the passages are provided by partitioning the hollow shell of the shaft longitudinally, the partitioning means extending substantially parallel with the shaft and extending between and separating the inlet and outlet ports of each of s'aid sets. An-

other object of my invention is to produce a hollow shaft having 'rabble arm inlet and outlet ports and having a non-diametral l partitionby which the shaft is divided into unequal cross-sectional portions, said partition extending between and separating said ports. Other objects of my invention'will be pointed out or will otherwise-appear in Fig. l.

The shaft illustrated is composed of longitudinal articulating sections of which two only are shown in Fig. 1. Each section consists of an outer cylindrical shell 3, pro` i vided with rabble arm inlet ports 4 and rabble arm' outlet ports 5, the adjacent ports v4, 5 constitutinga set through which a cooling 'medium is conducted torand from each rab-o ble arm 6, and the set or sets of portsin one horizontal plane being angularlyl disposed, as shown, at right angles, with reference to the set or sets in a plane longitudinally spaced from the first mentioned plane. The rabble arms are, of course, provided with the usual channels for the cooling medium and are secured to the shaft in any suitable and well known manner. -The rabble arms of central, longitudinal passage 8 are two si1ni lar partitions or vanes 9, which extend parallel with the shaft and the edges of which extend between the ports 4, 5 of each set and separate them so that eachport 4 is in communication with one of the passages 7 and each port 5 is in communication with the central passage 8. The partitions extend across the shaft preferably in the form of an are" and the edges of each partition are, as shown, 90 apart, one edge extendingbetween and separating the ports 4, 5 of one -set and the other edge extending between and separating the ports 4, 5 of another set which is longitudinally spaced from and angularly disposed with reference to the ports 4, 5 of the first mentioned set. The

partitions are preferably arcuate inform so the shell'or formed separately and then Secured to said shell, divide the shaftinto two channels 7 adapted for the passage of cooling vmedium before it has become heated and the central channel 8, adapted for the passage of the cooling medium after it has traversed the rabble arms and'has therefore becomev Fig. 2 is a cross-section* on the line 2--2 of In the operation ofthe furnacea suitable pascooling medium is vconducted into .the sages 7 from'which it passes through the various inlet ports into the arms, after traversing which it passes through the outlet ports 5 and enters the central passage 8 and finally escapes from said passage at the end `thcreof, the cooling medium being continuing its opposite edges extending between and separating the ports of said sets, said 'partition being uniformly spaced from the shell wall so as to constitute therewith a chamber of uniform cross section throughout the length of the partition.

2. A hollow shaft comprising an outer shell provided with aplurality of longitudinally spaced and angularly disposed sets of rabble arm inlet and outlet ports, the members of -a given set being angularly disposed in the same horizontal plane, and a non-diametr'al arcuate partition therein extending substantially parallel with the shell and having its opposite edges extending between and separating the ports of said sets, said partition being uniformly spaced 'from the shell wall so as to constitute therewith a chamber of uniform cross section throughout the length of the partition.

3. A hollow shaft 'comprising an outer shell provided with a plurality of longitudinally spaced and angularly disposed sets of rabble arm inlet and outlet ports, the members of a given set being angularly disposed in the same horizontal plane, anda non-diametral inwardly convexed partition I therein extending substantially parallel with the shell, opposite edges of said partition extending between and separating the ports of said sets.

4. A hollow shaft comprising an outer shellv with two pair of sets of rabble arm inlet and outlet ports, the members of a given set being also angularly disposed in the same horizontal plane and the sets of a given pair being angularly separated not to exceed 90, and a pair of non-diametral partitions therein extending substantially parallel to the shell, one edge of each partition extending between and separating the ports of certain sets of a pair and the opposite edge of said partition extending between and separating the ports of the remaining sets of the same pair.

5. A hollow shaft comprising an outer shell with two pair of sets of rabble arm inlet and outlet ports, the members of a given set being also angularly disposed in the same horizontal plane and the sets of a given pair being angularly separated not to exceed 90o, and a pair of non-diametral partitions therein extending substantially parallel to the shell, on'e edge of each'partition extending between and separating the portsof certain sets of a pair and the opposite edge of said partition extending between and sepa-v.` K

rating the ports of the remaining sets of the same pair, the combined cross sectional area of the passages formed between the partitions and the shell being less than the cross sectional area of the passage formed between the two partitions.

6. A hollow shaft comprising an outer shell provided with a plurality of longitudinally spaced sets of rabble arm inlet and outlet ports, theports of a given set being angularly disposed in the same horizontal plane, and a longitudinal partition therein extending substantially parallel with the shell and dividing the shell into two parallel and continuous longitudinal chambers of unequal cross section, opposite edges of said partition extending between and separating the ports of said sets.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses. f

DUDLEY BAIRD.

Witnesses F. BAIRD, E. L. KEoHaNE. 

